<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<div>
    <h1>注册页面</h1>
    <input type="text" placeholder="输入用户名" @blur="f()" v-model="user.username">{{info}}<br>
    <input type="password" placeholder="输入密码" v-model="user.password"><br>
    <input type="text" placeholder="输入昵称" v-model="user.nickname"><br>
    <input type="button" value="注册" @click="reg()">
</div>
<script src="https://cdn.bootcdn.net/ajax/libs/axios/0.21.1/axios.min.js"></script>
 <script src="https://cdn.staticfile.org/vue/2.2.2/vue.min.js"></script>
     <script>
         let v = new Vue({
             el:"body>div",
             data:{
                 user:{
                     username:"",
                     password:"",
                     nickname:""
                 },
                 info:""
             },
             methods:{
                 reg(){

                 },
                 f(){
                     axios.get("/check?username="+v.user.username)
                         .then(function (response) {
                             v.info=response.data
                         })
                     console.log("用户名："+v.user.username)
                 }
             }
         })
     </script>
</body>
</html>